Floor surfacing machines



une 14, 1955 7 5/ was: 462, Ilia. 64% 11 I 6 F QZ g F X w iii 0 178 6' United States Patent FLOOR SURFACING MACHINES Frank Philip Lalonde, Montreal, Quebec, Canada Application April 30, 1954, Serial No. 426,777

3 Claims. (Cl. 15-49) This invention relates to improvements in floor surfacing machines for scrubbing, waxing, polishing and the like treatment of such surfaces. it has to do with machines of the type which require the weight and balance directly over the work disc.

A machine of this type has been described in my coing said counter-shaft for rotation about its own axis and for swinging movement toward and away from the drive shaft and driven work shaft, said means including resilient biasing means normally tending to swing the counter-shaft and its mounting means away from the drive shaft and the work shaft.

A particular advantage of this arrangement is that it not only provides fora resilient tensioning of the belt connections which reduces wear on the belts but it also enables slackening or reduction of the tensionon the belt connections to any desired degree.

Another object is to provide a work surfacing machine of the character described with a novel arrangement of the component drive and driven shafts and. a swingably mounted counter-shaft with pulleys and belt connections carried thereby in which the counter-shaft is swingable toward the drive shaft and work shaft for removal of the belt connections therebetween without dismantling said shafts.

Still another object is to provide a lever arm mounting for said counter-shaft which is pivoted at one end for swinging movement of the counter-shaft and a resilient biasing means connected to said lever arm for outward swinging movement of said counter-shaft, said biasing means being adjustable for varying the amount of outward movement of the counter-shaft to control the degree of resilient tension on the belt connections.

The above and other objects, advantages and characteristic features of this invention will be more readily understood from the following detailed description taken in connection with the accompanying drawings, in which:

' Fig. 1 is a vertical sectional view of a machine embodying my invention.

Fig. 2 is a horizontal sectional view taken along the lines 2-2 of Fig. 1

Fig. 3 is a sectional view taken along the lines 3-3 of Fig. 2.

Referring more particularly to the drawings, 5 desig-. nates a housing for a reversible motor from which depends a shaft 6. Housing 5 is secured by screws 7 to the top of a casing 8 having a central opening 9 through which shaft 6 projects. A double grooved belt pulley 10 is fixed to rotate with shaft 6. Pulley 10 is con- More particularly nected by belts 11 to drive a second double grooved pulley 12 of larger diameter which is fixed to rotate with a counter-shaft 13 suspended from the rear of the casing. Counter-shaft 13 has a second double groove belt pulley 14 of lesser diameter fixed to rotate therewith below said first counter-shaft pulley 12. The driven pulley 14 is connected by belts 15 to a work disc driving pulley 16 mounted beneath and axially aligned with motor shaft 6. Although I have shown double grooved pulleys, this is only by way of example. It is to be understood that single or multiple grooved pulleys may be employed to decrease or increase the positive friction drive in proportion to the friction to be overcome be tween the work disc and working surface.

' Pulley 10 is partially enclosed by a vertical wall 17, depending from the under-side of casing 8 for a substantial distance below pulley 10 and having a side opening 18 for belts 11. A trunnion 19, provided with a top flange 21), is suspended from wall 17 by securing flange against the bottom of wall 17 with screws 22. The pulley 16 is fitted over trunnion 19 for free rotation through suitable bearings 23 which are force fitted in the bore of pulley 16. Pulley 16 is retained on trunnion 19 by means of a plate 24 underlying the inner race of bearings 23 and secured to the bottom of trunnion 19 by screws 25. Pulley 16 has a depending hub 26 and an intermediate shoulder 27. A cap 28 is fitted over the bottom of hub 26 and is secured thereto by screws 29. Cap 28 is provided with suitable means (not shown) which cooperate with a work disc retaining flange 32 for securing a work disc 33 to rotate with pulley 16.

As will be seen, particularly in Figs. 2 and 3, a lever arm 34 is pivotally secured to a thickened portion of the casing 8 by a'pivot pin 35. Arm 34 has a socket 36 on the upper side intermediate the length thereof and is provided with a central opening through which counter-shaft 13 extends. Shaft 13 has an enlarged or thickened intermediate portion 37 and a flange 38 which underlies the inner race of a bearing 39 to prevent movement of the shaft in the direction of its longitudinal axis. Bearing 39 is fitted in socket 36 and permits free rotation of shaft 13 relative to lever arm 34. The pulley 12 is mounted on the upper end of shaft 13 and is secured for rotation with the shaft by a set screw 40. Pulley 14 is fitted on the lower end of shaft 13 beneath arm 34 and is secured for rotation with the shaft by a set screw 41. A block 42 is pivotally secured to the underside of the free end of arm 34, as indicated at 43. An elongated adjusting rod 44 extends through an enlarged opening in the rear wall of casing 8 to permit angular movement relative thereto with its head 45 countersunk therein. Rod 44 has its shank portion slidably extended through a central opening in block 42, as indicated at 46. A compression spring 47 is disposed about the free threaded end of rod 44 between block 42 and a retaining nut 48 on the free threaded end of the rod. When the belts 11 and 15 are about the pulleys 12 and 14, the pull on lever arm 34 acting against spring 47 prevents rotation of nut 48 relative to rod 44. The resilient pressure on lever arm 34 protects both the pulleys and the belts. For example, when a foreign body comes therebetween the spring will absorb the shock of wedging of the body therebetween which would otherwise be encountered, if the arm was rigid.

When it is desired to increase the friction drive between the belts 11 and 15 and their respective pulleys 10-12 and 14-16, the rod 44 is rotated in one direction to move along the longitudinal axis of the nut so as to shorten the distance between the nut and rod head. This action applies resilient pressure to spring 47 against block 42, causing the latter to travel along the rod so 0 as to swing lever arm 34 and the pulleys carried thereby against the pulley belts.

To remove the belts or to reduce the friction thereon, rod 44 is counter-rotated to increase the distance betWeen the nut and rod head. This action releases the resilient pressure of spring 47 on block 42 so that block 42 will travel outwardly along rod 44, permitting a countor-swinging movement of the lever arm 34 to move the pulleys carried thereby out of frictional contact With the belts trained thereabout. When pressure is reduced to an extent which will permit sufficient inward swinging movement of arm 34 the belts may be removed with out dismantling the driving mechanism. Cover 50 is first removed. Then the belts 11 are removed, first by dropping the lower of the two belts from pulley 10 into the chamber 51 formed by extending the vertical wall 17 below the pulley 10. This belt is then withdrawn from chamber 51 and the upper belt is similarly removed and then both belts may be withdrawn through the opening in the casing provided by removal of cover 50. New

belts 11 are replaced in the reverse order.

In order to remove the belts 15, the work disc 32 is first removed from the hub 26. The two belts 15 will then be free for removal from the under side of the casing.

Although I have illustrated a preferred embodiment of this invention, it will be appreciated that changes and modifications may be resorted to without departing from the scope and spirit of the invention as defined by the appended claims.

What I claim is:

l. A rotary floor surfacing machine comprising a casing including a top wall and a depending side wall structure, a motor mounted over said casing and having a vertical drive shaft extending downwardly through an opening in the top wall of said casing, a pulley secured on said drive shaft to rotate therewith and positioned immediately beneath the top wall of said casing, a countershaft parallel to said drive shaft, a pulley on said counter-shaft to rotate about the axis of said countershaft, a pulley belt connection between said drive shaft pulley and said counter-shaft pulley for rotation of the latter about its axis of rotation, a second pulley on said counter-shaft beneath said first counter-shaft pulley and fixed to rotate with the latter about a common axis, a vertically disposed wall depending from the top wall of said casing and forming the peripheral side wall of a pulley housing containing said drive shaft pulley and having a side opening for the passage of the pulley belt connection, said vertical wall having its lower marginal portion extending below the lower edge of said drive pulley to provide a belt removal passage of a depth greater than the breadth of said pulley belt, a detachable trunnion mounted below said motor drive shaft in axial alignment therewith, said trunnion being provided with a top flange removably fitted against the lower edge of said vertical depending wall and forming the bottom wall of said drive shaft pulley housing, a work driving pulley rotatably supported on said trunnion, a second pulley belt connection between said second counter-shaft pulley and said work driving pulley for rotation of the latter, a floor surfacing element releasably connected to said work driving pulley for rotation therewith, and means mounting said counter-shaft for swinging move ment toward and away from the motor shaft and the trunnion, said last mentioned means including resilient biasing means normally tending to swing the countershaft and its mounting means from the motor shaft and the trunnion.

2. A rotary floor surfacing machine as set forth in claim 1, in which said biasing means is selectively adjustable to regulate the amount of swinging movement of said counter-shaft and its mounting means toward and away from said motor shaft and said trunnion.

3. A rotary floor surfacing machine as set forth in claim 1, in which said biasing means is adjustable to permit swinging movement of said counter-shaft and its mounting means toward said drive shaft and said trunnion for removal of said first and second pulley belts from the pulleys connected therewith, said casing top wall being provided with an opening and a removable cover therefor for withdrawal of said first mentioned pulley belt characterized in that said second mentioned pulley belt is withdrawn through the under side of said casing and in that said first mentioned pulley belt is removed from said drive pulley to said belt removal passage for withdrawal from the drive shaft pulley housing without removal of said trunnion, said casing top wall being provided with an opening for removal of said first mentioned pulley belt after its withdrawal from said drive shaft pulley housing.

References Cited in the file of this patent UNITED STATES PATENTS 1,059,879 Kennedy Apr. 22, 1913 2,246,683 Holt June 24, 1941 

